Our goal is to develop VTC-064 as a novel tolerance-inducing therapeutic to treat peanut allergy. Peanut allergy is one of the most common and potentially fatal forms of food allergy, affecting nearly three million Americans1. Unlike many food allergens, approximately 80% of individuals allergic to peanuts remain so throughout their lifetime2-5. Although several promising approaches to treat food allergies are in clinical development, the current options for treatment of peanut allergy are limited, and rely on strict avoidance6. For successful induction of tolerance, mucosal tissues play a significant role7-9. The epithelial layer that covers Gut Associated Lymphoid Tissue (GALT) and Nasopharyngeal Associated Lymphoid Tissue (NALT) regions contains a subpopulation of microfold cells (M cells) specialized to sample environmental antigens and present them to the adjacent immune cells10,11. A number of studies now confirm that these cells play a crucial role in the generation of tolerance to a given antigen12-15. VTC-064 is a recombinant protein composed of the reovirus head protein, ps1, fused to the peanut allergen (PNA), ara h 2. Ara h 2 is a dominant peanut allergen that is recognized by human immunoglobulin E in more than 90% of the patients who have peanut allergy16-18. Reoviruses are segmented, double-stranded RNA viruses that infect humans via mucosal surfaces. Since reoviruses bind to the M cells surface via ps 119,20, we have designed VTC-064 to use ps1 to target ara h 2 antigens specifically to M cells. Importantly, the ability of ps1-targeting to induce tolerance has been studied in both allergy and autoimmune models using oral and intranasal dosing routes12, 13, 21, and 22. The results from these studies demonstrate that ps1-mediated tolerance in antigen-sensitized mice, by both oral and intranasal routes of administration, is due to the induction of anti- inflammatory cytokines and an increase in suppressive regulatory T-Cells (Tregs)12,13,21,22. Our goal is to develop VTC-064 as an orally administered tolerance-inducing therapeutic for the rapid, effective treatment of peanut allergy. The proposed SBIR Phase 1 studies have three key objectives: 1) produce sufficient quantities of the VTC-064 (ara h 2-ps1) fusion protein; 2) determine the optimal oral dose of VTC-064 to induce tolerance in peanut sensitized mice; and 3) validate that oral administration of VTC-064 provides optimal efficacy over intranasal administration in mice.